1. Field of the Invention
The present invention generally relates to a tubular food casing, in particular a sausage casing, based on cellulose, which has a coated inner side for improved peelability. The invention furthermore relates to the coating solution used for this.
2. Description of Related Art
Untreated cellulose-based sausage casings conventionally adhere so strongly to the sausage filling, in particular to unsmoked or smoked emulsion for small sausages or simmered sausages, that they cannot be taken off without tearing the sausage filling surface.
Treated sausage casings, such as cellulose casings, which can be peeled more easily ("easy peel") are described in EP-A 0,502,432. These casings are coated on the inner side with alginate, alginic acid and/or chitosan. These release agents are similar to cellulose in their chemical structure. The coating is conventionally produced by charging with or spraying on a coating liquid. However, because of their high viscosity, alginate, alginic acid and chitosan cannot be sprayed in the amount which produces an optimal separation of the casing from the filling.
ES-A 549,161 describes the use of a mixture of lecithin and cellulose ether for coating cellulose sausage casings.
EP-A 0,502,431 discloses a particularly easily peelable cellulose casing having a coating which, in addition to alginate, chitosan and/or casein, further contains lecithin.
An easily removable cellulose-based sausage casing is also described in DE-A 2,227,438 (equivalent to U.S. Pat. No. 3,898,348). The casing is coated internally with a two-component mixture. One component is a water-soluble cellulose ether, the second an animal or vegetable oil, mineral oil, silicone oil and/or a water-soluble adduct of an alkylene oxide with a partial ester of a fatty acid.
The cellulose-based sausage casing according to DE-A 2,546,681 (equivalent to GB-A 1,470,726) has a similar internal coating. It contains as a first component a water-soluble cellulose ether, and as a second component a mixture of mono- and diglycerides of oleic acid. If required, a partial fatty acid ester of sorbitan or mannitan can additionally be used.
An internally coated sausage casing containing a mixture of mineral oil, an alkoxylated emulsifier sparingly soluble in mineral oil and an acetylated monoglyceride of a fatty acid is described in DE-A 2,300,338 (equivalent to U.S. Pat. No. 3,818,947).
Apart from the above-described cellulose-like compounds containing .beta.-glucosidic bonds, such as chitosan or alginate, up to now no other easy-peel active components have been disclosed.